The royal couple ― William and Harry’s grandparents ― aren’t the most expressive pair in public (you won’t see them engaging in PDA, like Meghan and Harry) but their love story is just about as romantic as they come.

“He was different than all the aristocratic rich young men Elizabeth had met previously. He had no money and no estates, but had royal blood in abundance ― they were cousins through Elizabeth’s great-grandmother Queen Victoria,” Seward told HuffPost. (Philip was originally a prince of Greece and Denmark, though he’d go on to abandon his Greek and Danish royal titles to marry into Britain’s royal family.)

Elizabeth developed a bit of a crush.

“Philip was so handsome, he was almost beautiful,” Seward said. “From the moment Elizabeth saw him again when she was 13 years old and he was 18, she never looked at another man.”

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The pair walk arm in arm in November 1947.

They wed in November 1947 when Elizabeth was 21. The marriage that followed is chronicled in Netflix’s popular drama series “The Crown,” which includes some pretty juicy details: The second season implies that in the mid-1950s, Philip had a fling with renowned ballerina Galina Ulanova.

Though Philip’s faithfulness has often been the subject of speculation, Seward said the ballerina plotline is more fiction than fact.

“Galina Ulanova did dance ‘Giselle’ for the queen on her first and only visit to the U.K., but the dancer was accompanied by her husband on the visit,” Seward said. “She never met Prince Philip, who left for his five-month tour a week after she arrived in the U.K.”

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The real royal couple and their "Crown" counterparts, played by Claire Foy and Matt Smith.

Seward noted that the real queen and her husband are far more interesting and nuanced than their on-screen characterizations on “The Crown.”

“The queen has much more humor than the character portrayed by Clarie Foy, and Prince Philip is far more determined, royal and masculine than the TV character,” she said. “They belong to an era that never showed emotion in public but in private, had many more laughs.”

What else is there to know about the queen and Philip’s private and public love story? Below, Seward and other royal experts take a look back on the royal couple’s biggest moments in 70 years of marriage.

The Engagement

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Elizabeth found Philip, who joined the Royal Navy and served in World War II, to be "dashing" and a breath of fresh air, Seward said.

From left to right: Princess Elizabeth, Philip, Queen Elizabeth (later, the Queen Mother), King George VI and Princess Margaret.

The Wedding

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The pair married on Nov. 20, 1947, at Westminster Abbey -- an event many in Great Britain anticipated greatly after many years of austerity and darkness during World War II.

"For months, the public was treated to tantalizing hints about the details of the bridesmaids’ dresses, and the cake and so on," Sarika Bose, a royal expert and a lecturer in Victorian literature at the University of British Columbia, told HuffPost. "Here you had this young couple that represented hope for a new, happier age after the war."

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With austerity measures still in effect, Elizabeth had to save up ration coupons to purchase the material for her wedding gown. Here, Elizabeth and Philip make their way down the aisle of Westminster Abbey, London, on their wedding day.

Royal Visits

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Philip and Elizabeth show off their square dance moves in 1951 in Ottawa, Canada, on one of many royal visits they made around the world. After the wedding, Philip had to to let go of many of his own career ambitions, Bose said.

"Prince Philip was reluctant to leave his career in the Royal Navy, as he was progressing well on his own steam," she said. "In marrying the woman who would be queen, he knew he would always have to compromise in many ways, starting with giving up a career in the Navy that suited his active personality."

Starting A Family

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In 1948, Philip and Elizabeth welcomed their firstborn, Prince Charles. Three more children would follow: their only daughter, Anne, and sons Andrew and Edward.

As the husband and consort of queen, Philip has never taken the job lightly. His friend and private secretary Michael Parker once recalled: “He told me his job, first, second and last, was never to let her down.”

Becoming Queen

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As depicted in "The Crown," Princess Elizabeth learned she would become queen while on an official visit to Kenya in 1952. Her father, King George VI, had died, and it was Philip's duty to relay the news, said Marlene Eilers Koenig, a royal historian who runs the blog Royal Musings.

"I can't imagine how difficult it was for Philip to be told that his father-in-law was dead and then have to take Elizabeth on a walk to break the news," Eilers Koenig said. "Not only that she was now queen, but that her beloved father had died."

The Coronation

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The newly crowned Queen Elizabeth II and Philip, Duke of Edinburgh, wave at the crowds from the balcony at Buckingham Palace. The 1952 coronation happened six years into their marriage and left the Duke a bit unsettled. Many accounts suggest that the couple held very traditional views about gender roles in marriage, despite Elizabeth's position.

"Suddenly, Elizabeth was the boss," Seward said. "She took great care to not to emasculate her husband and therefore behind the scenes, allowed him to make all the decisions. He was still the alpha male and according to all accounts, they had a loving and passionate, but private, relationship."

Adjusting To Their Roles

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The couple, pictured here at a polo match in 1957, had trouble adjusting to their new lives.

“Elizabeth had a lot to learn as queen and also had everyday jobs in addition to opening hospitals and other royal duties,” Bose said. “She was concerned for her husband’s need for a sense of identity and gave him duties. Eventually, he was able to establish several very worthy charity initiatives, like the Duke of Edinburgh’s Award.”

The Last Son

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In 1964, Elizabeth II and Philip welcomed their fourth and last child, Edward.

Protecting The Monarchy

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Philip has always been protective of his wife and the royal family's standing in the world, Seward said. That was particularly true following the very public divorces of their sons, Prince Charles (from Princess Diana, pictured here in pink) and Prince Andrew (from Sarah, Duchess of York) in 1996.

"The queen has always valued her husband's strong opinions and he was very protective of her and anyone who damaged the institution of the monarchy," Seward said. "He saw both Diana and Fergie’s behavior as damaging to the monarchy and, therefore, to his wife. They both devoted their life to duty at a cost to their personal life, but it was what they both felt they had to do."

Celebrations Later In Life

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Elizabeth — pictured here with Philip at St. Paul's Cathedral in London on her 90th birthday — acknowledged her husband's dedication to her during a celebratory speech to mark 60 years as queen.

"Prince Philip is, I believe, well-known for declining compliments of any kind. But throughout he has been a constant strength and guide," she said in 2012.

Their 70th Anniversary

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The royal couple — pictured in June 2017 with their children, grandchildren and great-grandchildren — recently celebrated their 70th anniversary.

"Their displays of affections have largely been confined behind the palace walls, but I am certain that there is great romance there," Eilers Koenig said. "It's still there, even now, after more than 70 years of marriage."